Atrial fibrillation is the most common arrhythmia to occur after coronary artery bypass graft (CABG) surgery. This arrhythmia occurs in approximately 1 in every 3 patients in this setting and the rate is even higher after valve or combined valve and CABG procedures. The majority of episodes of atrial fibrillation occur within the first 3 days after cardiac surgery and for those who have an initial episode of atrial fibrillation, the majority will go on to have another recurrence within 2 days of the first episode. Postoperative atrial fibrillation has been associated with an increase in neurological, renal and infectious complications as well as prolonged hospitalization and a significant increase in overall healthcare costs.